Massive MIMO-based Localization and Mapping Exploiting Phase Information of Multipath Components

In this paper, we present a robust multipath-based localization and mapping framework that exploits the phases of specular multipath components (MPCs) using a massive multiple-input multiple-output (MIMO) array at the base station. Utilizing the phase information related to the propagation distances of the MPCs enables the possibility of localization with extraordinary accuracy even with limited bandwidth. The specular MPC parameters along with the parameters of the noise and the dense multipath component (DMC) are tracked using an extended Kalman filter (EKF), which enables to preserve the distance-related phase changes of the MPC complex amplitudes. The DMC comprises all non-resolvable MPCs, which occur due to finite measurement aperture. The estimation of the DMC parameters enhances the estimation quality of the specular MPCs and therefore also the quality of localization and mapping. The estimated MPC propagation distances are subsequently used as input to a distance-based localization and mapping algorithm. This algorithm does not need prior knowledge about the surrounding environment and base station position. The performance is demonstrated with real radio-channel measurements using an antenna array with 128 ports at the base station side and a standard cellular signal bandwidth of 40 MHz. The results show that high accuracy localization is possible even with such a low bandwidth.Comment: 14 pages (two columns), 13 figures. This work has been submitted to the IEEE Transaction on Wireless Communications for possible publication. Copyright may be transferred without notice, after which this version may no longer be accessibl

Sensor Networks TDOA Self-Calibration: 2D Complexity Analysis and Solutions

Given a network of receivers and transmitters, the process of determining their positions from measured pseudo-ranges is known as network self-calibration. In this paper we consider 2D networks with synchronized receivers but unsynchronized transmitters and the corresponding calibration techniques,known as TDOA techniques. Despite previous work, TDOA self-calibration is computationally challenging. Iterative algorithms are very sensitive to the initialization, causing convergence issues.In this paper, we present a novel approach, which gives an algebraic solution to three previously unsolved scenarios. Our solvers can lead to a position error <1.2% and are robust to noise

Great Powers, the Persian Gulf, and Global Oil: A Comparative Analysis

Using original data, this study explores the changing capabilities of the United States, China, and Russia in the conflict-ridden Persian Gulf since 1980. It reveals what such shifts mean for American hegemony, the international distribution of capabilities in the region, relations among the great powers, and global oil security

Landlock

Landlock: Paralysing Dispute over Minerals on Adivasi Land in India explores the ways in which political controversy over a bauxite mining and refining project on constitutionally protected tribal lands in Andhra Pradesh descended into a state of paralysis where no productive outcome was possible. Long-running support for Adivasi (or tribal) land rights motivated a wide range of actors to block the project’s implementation by recourse to India’s dispersed institutional landscape, while project proponents proved adept in proposing workarounds to prevent its outright cancellation. In the ensuing deadlock, the project was unable to move towards completion, while marginalised Adivasi groups were equally unable to repossess their land. Such a ‘landlock’ is argued to be characteristic of India’s wider inability to deal with conflicts over land matters, despite the crucial importance of land for smallholder livelihoods and various economic processes in an intensely growth-focused country. The result has been frequent yet grindingly slow processes of contestation in which powerful business and state interests are, at times, halted in their tracks, but mostly seem able to slowly exhaust local resistance in their pursuit of large-scale projects that produce no benefits for the rural poor

The horses’ expression of emotions during interaction with humans : body language and facial expression

Many people are interacting with horses in different ways and for different reasons, as a hobby or professionally. Domestic horses are dependent on humans to understand and meet their needs, interpret their expression of emotions to recognize signs of negative emotions, and perhaps equally important, to recognize signs of positive emotions. It is widely accepted in research that animal welfare is more than just the absence of negative emotions, it is also about the presence of positive emotions. This puts a lot of pressure on humans to make sure the horses they take care of have a positive welfare. A review was made on what is currently known about how horses’ express emotions through body language and facial expressions. This was supplemented by a survey asking people actively involved with horses which emotions they think horses can experience, which emotions they have seen horses express, and how much attention they pay to a horse’s expression of emotions when interacting with them. Horses can most likely experience every emotion and mood that humans can. The respondents of the survey did not quite agree with the literature review on which emotions horses can experience. Animals’ emotions and moods are important parts of their welfare, and this is why humans interacting with horses should have knowledge about which emotions they can experience and how they are expressed. To promote positive emotions in horses, humans need knowledge on what brings them out and how to recognize them. To recognize how certain emotions are expressed could also contribute to safer human-horse interactions. Keywords: horse, emotion, mood, facial expression, body language, welfare, interaction, huma